You don't lose unspent red mana as steps and phases end.
Magecraft ŃĘWhenever you cast or copy an instant or sorcery spell, discard a card, then draw a card. If this is the second time this ability has resolved this turn, Ashling, Flame Dancer deals 2 damage to each opponent and each creature they control. If it's the third time, add RRRR.
NM-Mint Foil - $10.60
Lightly Played Foil - $10.10
Moderately Played Foil - $9.50
Heavily Played Foil - $8.50
Damaged Foil - $6.90
NM-Mint Foil Non English - $10.60
Lightly Played Foil Non English - $10.10
Moderately Played Foil Non English - $9.50
Heavily Played Foil Non English - $8.50
Damaged Foil Non English - $6.90